1. Field of the Invention
The present invention relates to an apparatus for manufacturing a semiconductor layer, by performing rapid thermal processing(RTP), and more particularly, to an apparatus capable of heating the wafer rapidly, exactly and uniformly and measuring the heating temperature of the wafer by measuring the length of the expansion of the wafer.
2. Description of the Prior Art
In a conventional apparatus for processing the wafer, it heats the wafer using light energy from a lamp. Light energy is converted into thermal energy which is absorbed in the wafer, so that thermal energy is transmitted to all areas on the wafer. Also, the temperature of the wafer is measured by using thermal energy radiated from the wafer as a pyrometer.
However, in the conventional apparatus, since the wafer has a non-uniform surface due to films and patterns, which are formed on the wafer, light energy is non-uniformly absorbed in the wafer. Also, the temperature of the wafer can't be exactly measured because thermal energy is non-uniformly radiated in accordance with films deposited on the wafer, impurity levels, the chamber reflect ratio, surface roughness, and the like.